The recipient, Rev. J. H. Edgar, was headmaster of Temple Grove School, East Sheen. 2pp., 12mo. Bifolium. In good condition, lightly aged, with light traces of glue from mount to blank reverse of second leaf. An interesting letter, casting light on the collaborative process of Victorian taxonomy. Owen is 'truly obliged' to Edgar and his 'friend Mr. Mayor' (the classical scholar J. E. B. Mayor of St John's College, Cambridge?), and will 'adopt his suggested Tritylodon for my pet Mammal – the oldest geologically, that has yet been discover'd.' The name is 'not strictly or literally applicable', but 'the tooth-knobs' are many, 'being 3 in a row, in each sort of every tooth', so it 'answers as well as most of our generic names from that wonderful Greek' (last word underlined twice). Postscript, signed 'R. O', on second page: '”Aetiodactyle”, and, “Perissodactyle” - both issues of “Temple Grove”, are now “household words” with every Naturalist in Europe & America.'